Method of manufacturing a hollow body used in an image forming apparatus

摘要

A method of manufacturing a hollow body having an external surface randomly provided with a large number of depressions is provided. The method includes providing the large number of depressions on the external surface of the hollow body. A profile curve of the external surface in a circumferential direction is obtained while rotating the hollow body. A frequency analysis is performed on the obtained profile curve. A quality of the hollow body is judged by comparing a result of the frequency analysis with a predetermined judgment standard.